Any asset that was directly owned by WMB or pledged to it could have been seized and sold to JPM. Whether that actually happened this way has different interpretations here.
SH assets are different in that it sets out a specific way assets originated by WMb can be immune to seizure by the FDIC. Once that process is followed the asset is protected by SH rules.
IMO, virtually all MBS's securitized by WMAAC and WMMSC etc and transferred to Trusts are protected. Whether SH is moot depends on if those SPE's and/or WMI/WMIIC retained interests in those MBS's.
Based on my initial post re Available for Sale Securities, it is clear WAMU retained securitized products which they could liquidate if required, and as of June, 2008 these accounted for ~$24.4B worth.
If they did, that property was NOT among the assets sold to JPM, nor could the FDIC seize same to pay claims against the Receivership. Our problem is we don't have access to all the information.
Download pdf in link below for explanation of FDIC Safe Harbor provisions. (pgs 3-7).